Public Opinion Polling
How Public Opinion is Measured
(and Mismeasured)
Rise of Polling Companies
• Originated with market research
– Gallup dissertation
• Early Political Polling
– Election forecasting
– Literary Digest polls
• Correctly predicted winner of presidential elections
from 1916 to 1932
• Conducted VERY large mail-in surveys (drawn
from telephone and automobile ownership rolls)
Rise of the Gallup Poll
• 1936 Election
– Literary Digest vs. Gallup
• Gallup predicted not only that he would get it
right with a sample of approximately 1,500
respondents (as opposed to over 10 million),
but that Literary Digest would get it wrong
• Gallup used quota sampling methods and
face-to-face interviews
Polling Techniques
• Literary Digest to the Representative Sample
– Mail-in surveys to face-to-face interviews
– We can now get accurate public opinion data from as
few as 1,500 respondents (under right conditions)
• Polling techniques have changed as technology
has advanced
– Face-to-face interviews to telephone surveys
• Telephone databases
– Early telephone surveys to sophisticated telephone
polling (automated systems)
Future Polling Techniques?
• Internet polling
– Today, internet polling is very unscientific
• Self-Selection Bias
– Impossible to get random sample of population
– For that matter, any call-in TV poll is also unscientific
and worthless
– In order for internet polling to become a valid method
for measuring public opinion, pollsters would need to
find ways of generating a random sample of the
population
• Particularly difficult given that internet users as a whole are a
specific segment of electorate/citizenry
Use of Polls in Politics:
Dewey Defeats Truman
• 1948 Election
– Gallup predicted that
Republican Thomas
Dewey would defeat
incumbent president
Harry Truman
– Gallup, Roper,
Crossley stopped
polling about a week
before general election
• Still many undecided
voters
Use of Polls in Politics:
Confidence in Polling Restored
• Louis Harris
– John Kennedy hired Harris to be his
campaign pollster
• Humphrey was vulnerable in West Virginia and
Wisconsin
• Harris was the first pollster to be employed by a
president
– Kennedy kept him on to gauge public approval ratings
and policy preferences
Use of Polls in Politics
• Johnson
– Used polling data to measure public support for his domestic
agenda
– Especially concentrated on public opinion late in his presidency,
as he was extremely concerned with perception of U.S.
involvement in Vietnam.
– In 1966, Johnson’s nightly reading included summarized results
of a series of questions relating to public support for the war.
• Nixon
– In his first year in office, Nixon commissioned more private polls
than Johnson commissioned during his entire presidency
– Extensive polling during 1972 re-election campaign
Use of Polls in Politics
• Ford
– Examined strategies for maneuvering out of the
political hole left by the Watergate scandal
• Tried to gauge public opinion about the possibility of
pardoning Nixon
• Carter
– Felt that public opinion was so important that he gave
his pollster an office in the White House
• The beginning of a much more common trend among recent
presidents
• Hostage crisis at end of his presidency consumed much of
his time and polling attention
Use of Polls in Politics
• Reagan
– Met with his pollster almost monthly to monitor public support for
the administration and its policies
• George H.W. Bush
– Kept close tallies on public opinion and reportedly relied on poll
results to shape his posture with respect to Iraq.
• Clinton
– “Horserace presidency”
– Made no secret about the role of pollsters in his White House,
commissioning regular polls about every aspect of American
political life (Stanley Greenburg and later from Dick Morris)
– Morris – Clinton did not used polls to select his policies
• Used polls to determine which actions were winning the most
support and to shape public messages
Use of Polls in Politics
• 2000 Election
– Methods for polling today are extremely
accurate
– Enormous number of polling companies, even
larger number of polls
• Large polling companies (Gallup, etc.)
• Polling alliances
– On average, these polls were extremely
accurate (missed by about one percentage
point)